Berlin
BerlinFlash 90

Berlin police said on Tuesday they were unable to rule out an Islamist background in a New Year’s Eve knife attack in one of the German capital's underground stations, AFP reported.

The attack was carried out by a Syrian knifeman described as "deranged".

Witnesses said the 23-year-old, identified as Ahmad Al-H., attacked several people with a knife "for no apparent reason" at the Bayerischer Platz station in southwestern Berlin on New Year's Eve.

The Tagesspiegel newspaper reported that he had asked one 50-year-old German man his nationality and called him an "infidel" before stabbing him.

The man suffered a light injury but declined medical treatment, police said, according to AFP.

Other people attacked by the knife wielder including a mother with a young child escaped unharmed, according to Tagesspiegel.

Police has only said that the attacker - who the paper reported was known to officers after being involved in several brawls - "seemed deranged" when they arrested him in response to emergency calls.

Following the arrest, officers brought the knifeman to a clinic and had him examined by a psychiatrist.

"We can't confirm or deny (the reports), we are checking whether there may be an Islamist background," a police spokesman told AFP.

Germany has been on high alert following a series of attacks in the country.

In one attack, a 17-year-old Afghani with an axe attacked passengers on a train in Wurzburg before being shot dead by security forces.

In a second incident, an attacker set off a bomb in a restaurant in Ansbach, killing himself and wounding 12 others.

The most serious attack took place last December, when terrorist Anis Amri drove a truck into a Christmas market in Berlin, killing 12 people and injuring 48. The Islamic State (ISIS) later claimed responsibility for the attack.

Last week, German prosecutors charged an alleged member of ISIS who spent time in Syria with membership in a terrorist organization and committing a war crime.